Blood circulating microparticle species in relapsing-remitting and secondary progressive multiple sclerosis. A case-control, cross sectional study with conventional MRI and advanced iron content imaging outcomes

BACKGROUND

Although multiple sclerosis (MS) is thought to represent an excessive and inappropriate immune response to several central nervous system (CNS) autoantigens, increasing evidence also suggests that MS may also be a neurovascular inflammatory disease, characterized by endothelial activation and shedding of cell membrane microdomains known as 'microparticles' into the circulation.

OBJECTIVE

To investigate the relationships between these endothelial biomarkers and MS.

METHODS

We examined the relative abundance of CD31(+)/PECAM-1, CD51(+)CD61(+) (αV-β3) and CD54(+) (ICAM-1) bearing microparticles in sera of healthy individuals, patients with relapsing-remitting MS, and secondary-progressive MS. We also investigated the correlation among circulating levels of different microparticle species in MS with conventional MRI (T2- and T1-lesion volumes and brain atrophy), as well as novel MR modalities [assessment of iron content on susceptibility-weighted imaging (SWI)-filtered phase].

RESULTS

Differences in circulating microparticle levels were found among MS groups, and several microparticle species (CD31(+)/CD51(+)/CD61(+)/CD54(+)) were found to correlate with conventional MRI and SWI features of MS.

CONCLUSION

These results indicate that circulating microparticles' profiles in MS may support mechanistic roles for microvascular stress and injury which is an underlying contributor not only to MS initiation and progression, but also to pro-inflammatory responses.

Progressive multifocal leukoencephalopathy: a review of the neuroimaging features and differential diagnosis

Progressive multifocal leukoencephalopathy (PML) is an uncommon and often fatal demyelinating disease of human central nervous system, which is caused by reactivation of the polyomavirus JC (JCV). PML generally occurs in patients with profound immunosuppression such as AIDS patients. Recently, a number of PML cases have been associated with administration of natalizumab for treatment of multiple sclerosis (MS) patients. Diagnosis and management of PML became a major concern after its occurrence in multiple sclerosis patients treated with natalizumab. Diagnosis of PML usually rests on neuroimaging in the appropriate clinical context and is further confirmed by cerebrospinal fluid polymerase chain reaction (PCR) for JCV DNA. Treatment with antiretroviral therapies in HIV-seropositive patients or discontinuing natalizumab in MS patients with PML may lead to the development of immune reconstitution inflammatory syndrome (IRIS) which presents with deterioration of the previous symptoms and may lead to death. In patients under treatment with monoclonal antibodies in routine practice, or new ones in ongoing clinical trials, differentiating PML from new MS lesions on brain MRI is critical for both the neurologists and neuroradiologists. In this review, we discuss the clinical features, neuroimaging manifestations of PML, IRIS and neuroimaging clues to differentiate new MS lesions from PML. In addition, various neuroimaging features of PML on the non-conventional MR techniques such as diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), and MR spectroscopy (MRS) are discussed.

Dalfampridine: review of its efficacy in improving gait in patients with multiple sclerosis

Multiple sclerosis (MS) is a progressive immune-mediated neurodegenerative disease of human central nervous system (CNS), which causes irreversible disability in young adults. The cause and cure for MS remain unknown. Pathophysiology of MS includes two arms: inflammatory demyelination and neurodegeneration. The inflammatory demyelination of MS which is mainly promoted by a massive activation of the immune system against putative CNS antigen(s) leads to loss of oligodendrocyte/myelin complex which slows down or halts impulse conduction in denuded axons. Practically, loss of myelin significantly reduces signal conduction along the demyelinated axons through alterations in the distribution of axonal ion channels. Dalfampridine (4-aminopyridine or 4-AP) is an oral potassium channel blocker, which was recently approved by FDA for symptomatic treatment of MS. Dalfampridine, which acts at the central and peripheral nervous systems, enhances conduction in demyelinated axons and improves walking ability of MS patients. A number of clinical trials have evaluated the safety and efficacy of fampridine in MS patients with the degree of gait improvement as the main outcome. The objective of this manuscript is to provide an overview of the pharmacology, pharmacokinetics, clinical trials, side effects and interactions of dalfampridine used in treatment of MS patients.

Differential cytokine responses in human and mouse lymphatic endothelial cells to cytokines in vitro

BACKGROUND

Inflammatory cytokines dysregulate microvascular function, yet how cytokines affect lymphatic endothelial cells (LEC) are unclear.

METHODS AND RESULTS

We examined effects of TNF-α, IL-1 beta, and IFN-gamma on LEC proliferation, endothelial cell adhesion molecule (ECAM) expression, capillary formation, and barrier changes in murine (SV-LEC) and human LECs (HMEC-1a).

RESULTS

All cytokines induced ICAM-1, VCAM-1, MAdCAM-1, and E-selectin in SV-LECs; TNF-α, IL-1 beta; and IFN-gamma induced ECAMs (but not MAdCAM-1) in HMEC-1a. IL-1 beta increased, while IFN-gamma and TNF-α reduced SV-LEC proliferation. While TNF-α induced, IFN-gamma decreased, and IL-1 beta did not show any effect on HMEC-1a proliferation. TNF-α, IL-1 beta, and IFN-gamma each reduced capillary formation in SV-LEC and in HMEC-1a. TNF-α and IL-1 beta reduced barrier in SV-LEC and HMEC-1a; IFN-gamma did not affect SV-LEC barrier, but enhanced HMEC-1a barrier. Inflammatory cytokines alter LEC growth, activation and barrier function in vitro and may disturb lymphatic clearance increasing tissue edema in vivo.

CONCLUSION

Therapies that maintain or restore lymphatic function (including cytokines blockade), may represent important strategies for limiting inflammation.

Alterations in serum MMP-8, MMP-9, IL-12p40 and IL-23 in multiple sclerosis patients treated with interferon-β1b

Background: Interferon-β1b (IFN-β1b), an effective treatment for multiple sclerosis (MS), lessens disease severity in MS patients. However, the mechanisms of its immunoregulatory and anti-inflammatory effects in MS remain only partially understood. Matrix metalloproteinases (MMP) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) are involved in blood brain barrier disruption and formation of MS lesions. Th1/Th17 cytokines e.g. interleukins IL-12p40, IL-17, and IL-23, are associated with MS disease activity and are significant players in pathogenesis of MS.

Objective: During a 1-year prospective study, we serially measured serum MMP-8, MMP-9, TIMP-1, IL-12p40, IL-17, and IL-23 in 24 patients with relapsing—remitting MS. We compared the results to clinical course and to brain magnetic resonance imaging. IFN-β1b decreased serum MMP-8 and MMP-9 (not TIMP-1).

Results: The sustained treatment with IFN-β1b attenuated the pro-inflammatory environment by significantly reducing the serum IL-12p40, IL-23, and showed a trend for decreasing IL-17. Decreased serum MMP-8, MMP-9, IL-12 and IL-23 levels were correlated with a decrease in the number of contrast-enhanced T2-weighted lesions.

Conclusion: Early treatment of MS with IFN-β1b may stabilize clinical disease by attenuating levels of inflammatory cytokines and MMPs. Serial measurement of inflammatory mediators may serve as sensitive markers to gauge therapeutic responses to IFN-β1b during the first year of treatment.

Increasing female preponderance of multiple sclerosis in Isfahan, Iran: a population-based study

There is an overall increase in the worldwide prevalence and incidence of multiple sclerosis (MS). Studies from several countries also demonstrated an increase of female/male ratio over time denoting an increase in the incidence of MS particularly in women. In this study we sought to assess the trends in MS incidence and prevalence in males and females over recent decades in Isfahan, Iran, which differs from other regions in terms of environmental and lifestyle changes. We determined female/male ratio by year of birth (YOB) in 1584 patients with MS registered with Isfahan Multiple Sclerosis Society (IMSS) from April 2003 to August 2007. A comparison of sex ratio of MS patients by YOB showed a significant, progressive, gradual increase, with an apparent interruption in the late 1960s. In this study year of birth is a significant predictor for sex ratio ( p < 0.001, χ2 = 17.130, Spearman’s rank correlation r = 0.893). Our findings show that there is a significant increase in the incidence of MS among females for the the last decades in the Isfahan province of Iran. This rapid increase may be related to changes in environmental interactions rather than genetic factors, and among them vitamin D insufficiency, enhanced diagnosis, and lifestyle changes appear to be more plausible causative factors.

Pathophysiology of the lymphatic drainage of the central nervous system: Implications for pathogenesis and therapy of multiple sclerosis

In most organs of the body, immunological reactions involve the drainage of antigens and antigen presenting cells (APCs) along defined lymphatic channels to regional lymph nodes. The CNS is considered to be an immunologically privileged organ with no conventional lymphatics. However, immunological reactions do occur in the CNS in response to infections and in immune-mediated disorders such as multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE). Here, we review evidence that cervical lymph nodes play a role in B and T cell mediated immune reactions in the CNS. Then we define the separate pathways by which interstitial fluid (ISF) and CSF drain to cervical lymph nodes. ISF and solutes drain from the brain along the 100-150nm-wide basement membranes in the walls of capillaries and arteries. In humans, this perivascular pathway is outlined by the deposition of insoluble amyloid (Abeta) in capillary and artery walls in cerebral amyloid angiopathy in Alzheimer's disease. The failure of APCs to migrate to lymph nodes along perivascular lymphatic drainage pathways may be a major factor in immunological privilege of the brain. Lymphatic drainage of CSF is predominantly through the cribriform plate into nasal lymphatics. Lymphatic drainage of ISF and CSF and the specialised cervical lymph nodes to which they drain play significant roles in the induction of immunological tolerance and of adaptive immunological responses in the CNS. Understanding the afferent and efferent arms of the CNS lymphatic system will be valuable for the development of therapeutic strategies for diseases such as MS.

Interferon (IFN)-ß1a and IFN-ß1b Block IFN-?-Induced Disintegration of Endothelial Junction Integrity and Barrier

Recent clinical trials indicate the efficacy of interferon (IFN)-beta 1b in reducing relapse rate in relapsing-remitting multiple sclerosis (MS), whereas a surge of IFN-gamma precedes and provokes acute relapses. Disruption of the cerebral endothelial barrier and transendothelial migration of inflammatory cell migration into the brain play a significant role in pathogenesis of MS and may be driven by this surge in IFN-gamma. However, the molecular mechanisms underlying the beneficial effects of IFN-beta 1b against the deleterious effects of IFN-gamma on the barrier formed by the junctional proteins remain to be characterized. The authors investigated the effects of IFN-beta 1b, IFN-beta 1a, and IFN-gamma on the integrity of two endothelial junctional proteins, occludin and vascular endothelial-cadherin (VE-cadherin). Human umbilical vein endothelial cell (HUVEC) layers were treated with IFN-beta 1b, IFN-beta 1a, IFN-gamma, IFN-beta 1b plus IFN-gamma, or IFN-beta 1a plus IFN-gamma. IFN-beta 1b, IFN-beta 1a, and IFN-gamma effects on occludin and VE-cadherin integrity and electrical resistance were assessed by Western blotting and immunofluorescence. IFN-gamma significantly reduced occludin expression and produced gaps in endothelial monolayers. VE-cadherin expression was decreased to a lesser extent in endothelial cells exposed to IFN-gamma. IFN-beta 1b significantly attenuated the IFN-gamma-induced decrease in occludin and VE-cadherin expression. The protective effects of IFN-beta 1a on IFN-gamma-treated endothelial cells were similar to those of IFN-beta 1b. IFN-gamma also significantly reduced endothelial monolayer electrical resistance; this effect was blocked by either IFN-beta 1a or IFN-beta 1b. IFN-beta 1a and IFN-beta 1b effectively prevent the IFN-gamma-induced disintegration of the endothelial tight junctions and sustain barrier against the effects of IFN-gamma. The protective effects of IFN-beta on occludin and VE-cadherin stability appear to represent molecular mechanisms for the therapeutic effects of the IFN-beta on blood brain barrier in MS.

Volumetric Examination of MS Plaques and Correlation with EDSS Ratings

This study is a retrospective analysis of 17 patients with multiple sclerosis. The total volume of plaques from three different MR image sets of the brain was correlated with the EDSS ratings of the patients. Each of the correlations showed a positive relationship, but none was statistically significant. A more extensive study is required in order to give significance to these relationships.

Gray matter pathology in (chronic) MS: modern views on an early observation

Involvement of the gray matter (GM) in the pathology of multiple sclerosis (MS) was already recognized in the early days of MS research, but the detection of (cortical) GM lesions under the microscope and with magnetic resonance imaging (MRI) techniques was initially suboptimal and could only recently be enhanced. The visualization of GM lesions in vivo opens new doors for studies focusing on clinical, especially cognitive, effects of GM pathology, as well as for monitoring of neuroprotective treatment. However, so far little is known about what causes GM pathology. In this review, several pathogenetic mechanisms will be discussed, affecting the MS brain both from the 'outside-in' and from the 'inside-out'. Also, the use and reliability of MRI atrophy measures as a monitoring tool for GM damage in the therapeutic setting will be reviewed.

Mechanisms of action of disease-modifying agents and brain volume changes in multiple sclerosis

Disease-modifying agents (DMAs), including interferon beta (IFNbeta) and glatiramer acetate (GA), are the mainstays of long-term treatment of multiple sclerosis (MS). Other potent anti-inflammatory agents like natalizumab and different types of chemotherapeutics are increasingly being used for treatment of MS, particularly in patients with breakthrough disease activity. Brain volume (BV) loss occurs early in the disease process, accelerates over time, and may be only partially affected by DMA therapy. Low-dose, low frequency IFNbeta administered once weekly and GA appear to partially reduce BV decline over the second and third years of treatment. High dose, high frequency IFNbeta demonstrated no clear effect on BV loss during this time period. Current evidence suggests that changes in BV after immunoablation may not be due entirely to the resolution of edema but may be related to potential chemotoxicity of high dose cyclophosphamide. Natalizumab reduces the development of BV decline in the second and third years of treatment. IV immunoglobulin showed a positive effect on decelerating BV reduction in relapsing and advanced stages of MS. These differences between DMAs may be explained by the extent of their therapeutic effects on inflammation and on the balance between inhibition or promotion of remyelination and neuronal repair in the CNS. We described the mechanisms of action by which DMAs induce accelerated, non-tissue-related BV loss (pseudoatrophy) in the short term but, in the long run, may still potentially lead to permanent BV decline. The effects of corticosteroid therapy on changes in BV in patients with MS help clarify the mechanisms through which potent anti-inflammatory treatments may prevent, stabilize, or induce BV loss.

N-methyl-d-aspartate receptor activation in human cerebral endothelium promotes intracellular oxidant stress

Cerebral endothelial cells in the rat, pig, and, most recently, human have been shown to express several types of receptors specific for glutamate. High levels of glutamate disrupt the cerebral endothelial barrier via activation of N-methyl-d-aspartate (NMDA) receptors. We have previously suggested that this glutamate-induced barrier dysfunction was oxidant dependent. Here, we provide evidence that human cerebral endothelial cells respond to glutamate by generating an intracellular oxidant stress via NMDA receptor activation. Cerebral endothelial cells loaded with the oxidant-sensitive probe dihydrorhodamine were used to measure intracellular reactive oxygen species (ROS) formation in response to glutamate receptor agonists, antagonists, and second message blockers. Glutamate (1 mM) significantly increased ROS formation compared with sham controls (30 min). This ROS response was significantly reduced by 1) MK-801, a noncompetitive NMDA receptor antagonist; 2) 8-( N, N-diethylamino)- n-octyl-3,4,5-trimethoxybenzoate, an intracellular Ca2+antagonist; 3) LaCl3, an extracellular Ca2+channel blocker; 4) diphenyleiodonium, a heme-ferryl-containing protein inhibitor; 5) itraconazole, a cytochrome P-450 3A4 inhibitor; and 6) cyclosporine A, which prevents mitochondrial membrane pore transition required for mitochondrial-dependent ROS generation. Our results suggest that the cerebral endothelial barrier dysfunction seen in response to glutamate is Ca2+dependent and may require several intracellular signaling events mediated by oxidants derived from reduced nicotinamide adenine dinucleotide oxidase, cytochrome P-450, and the mitochondria.

MAdCAM-1 expression and regulation in murine colonic endothelial cells in vitro

BACKGROUND

Although the mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is associated with the etiology of inflammatory bowel diseases, few studies have directly examined MAdCAM-1 using microvascular endothelium derived from the colon. This study measured the expression of MAdCAM-1 in a novel colon endothelial line MJC-1, as well as MAdCAM-1 regulation and function in vitro.

METHODS

We cloned microvascular endothelial cells from primary colon cultures using ImmortoMice mice (whose cells express a temperature-sensitive SV40 large T antigen, H-2Kb-tsA58 mice). Expression of MAdCAM-1 after stimulation with cytokines [tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, or interferon (IFN)-gamma] was determined by Western blotting. Signal paths regulating MAdCAM-1 expression were examined using pharmacological blockers before cytokines. We also examined lymphocyte adhesion using lymphocytes that constitutively express alpha4beta7 integrin.

RESULTS

TNF-alpha induced MAdCAM-1 in a dose-dependent manner by 24 hours. MAdCAM-1 induction was protein kinase C, tyrosine kinase, p38 mitogen activated protein kinase, and nuclear-factor kappa-B/poly adenosine diphosphate ribose polymerase dependent. Lymphocyte adhesion was increased 2.6-fold after TNF-alpha stimulation and was inhibited by anti-MAdCAM-1 antibody before treatment (P < 0.05 control versus TNF-alpha).

CONCLUSIONS

In vitro, MAdCAM-1 can be induced on colon endothelial cells by TNF-alpha stimulation and may represent a useful model to study microvascular injury in the large intestine.

Analytic approaches to differential gene expression in AIDS versus control brains

We previously showed that specific strains of human immunodeficiency virus (HIV)-1 infect the brain and contribute to Neuropathology, Cognitive Distress, and Neuropsychiatric Disease. To study further brain disease that results from HIV-1 infection, we commenced analysis of changes in gene expression in brain. We analyzed RNA purified from Frontal Cortex of 5 HIV-1 infected and 4 HIV-1 negative control subjects RNA was amplified and Affymetrix technology was used to analyze gene expression using the 12,585 gene Affymetrix Human Genome U95A chip. The expressed genes showed highly significant Pearsons correlations with each other within the two groups. Expression intensities were transferred to Microsoft Excel and Spotfire was used to analyze the results. Twenty-group K-means cluster analysis was done for HIV+ and HIV- subjects. Genes that were expressed in the same cluster numbers in the two groups were removed from further analysis. Analysis of Gene expression in the top 13 HIV+ clusters showed expression in the 40 gene categories designated in our prior studies. Genes from several categories occurred in more than one K-means cluster. Genes identified in these lists included several genes that have been previously studied: MBP, Myelin-PLP, NMDA receptor, MAG, astrocytic protein, Notch 3, APP, Senescence, proteasome, Ferritin, signaling, cell cycle, iNOS, Chemokine, splicing, synapse, protein tags, and ribosomal proteins. The first (primary significant) axis of both Principal Component Analyses ordered the genes in the same patient groups as the K-means cluster analysis for the respective patient groups. PCA was thus not more informative than K-Means cluster analysis. Ratios of HIV+ to HIV- intensities were calculated for all the averaged gene expression intensities. The ratio range was 0.14 to 9.26. The genes at the extremes (ad extrema) did not correspond to the gene order by K-means clustering (or PCA). The genes in the top 13 K-means clusters showed low-level changes by expression ratio. Genes ad extrema by ratio were in clusters with very large memberships. Mann-Whitney analysis confirmed expression ratio results. Several inferences result from our preliminary study. First, study design will be different in future studies involving additional replicates. Second, ratios inform us of the extent of changes in gene expression quantitatively. Third, Cluster methodology provides us with more subtle information, how bunches (clusters) of genes behave in terms of their centroids (attractors). Fourth, genes that change extensively by ratio tend to be in the larger k-Means clusters. We conclude that ranking gene expression with the use of expression ratio or by K-means clustering, yield different representations of the data.

An occipital lobe epileptogenic focus in a patient with West Nile encephalitis

Although most human cases of West Nile (WN) fever are benign, approximately 1% produce severe neurological illness. Meningitis and/or encephalitis comprise 75% of hospitalized cases with seizures in 10-15%. Occipital lobe seizures, often mimicking other primary seizure types due to extra-occipital spread, is uncommon in adults and especially so from an infectious origin. A case of WN encephalitis presenting with a simple partial seizure, focal motor, resulting from an occipital epileptogenic focus is reported. The atypical epileptogenic location of the case and the observed frequency of seizures in WN encephalitis suggest that this virus is particularly irritative to cortical neuronal networks. Thus when seizures especially with atypical EEG patterns present during an acute febrile illness in the warmer months, WN encephalitis should be considered.

Glutamate causes a loss in human cerebral endothelial barrier integrity through activation of NMDA receptor

l-Glutamate is a major excitatory neurotransmitter that binds ionotropic and metabotropic glutamate receptors. Cerebral endothelial cells from many species have been shown to express several forms of glutamate receptors; however, human cerebral endothelial cells have not been shown to express either the N-methyl-D-aspartate (NMDA) receptor message or protein. This study provides evidence that human cerebral endothelial cells express the message and protein for NMDA receptors. Human cerebral endothelial cell monolayer electrical resistance changes in response to glutamate receptor agonists, antagonists, and second message blockers were tested. RT-PCR and Western blot analysis were used to demonstrate the presence of the NMDA receptor. Glutamate and NMDA (1 mM) caused a significant decrease in electrical resistance compared with sham control at 2 h postexposure; this response could be blocked significantly by MK-801 (an NMDA antagonist), 8-(N,N-diethylamino)-n-octyl-3,4,5-trimethyoxybenzoate (an intracellular Ca2+ antagonist), and N-acetyl-L-cystein (an antioxidant). Trans(+/-)-1-amino-1,3-cyclopentanedicarboxylic acid, a metabotropic receptor agonist (1 mM), did not significantly decrease electrical resistance. Our results are consistent with a model where glutamate, at excitotoxic levels, may lead to a breakdown in the blood brain barrier via activation of NMDA receptors.

Human neuroepithelial cells express NMDA receptors

L-glutamate, an excitatory neurotransmitter, binds to both ionotropic and metabotropic glutamate receptors. In certain parts of the brain the BBB contains two normally impermeable barriers: 1) cerebral endothelial barrier and 2) cerebral epithelial barrier. Human cerebral endothelial cells express NMDA receptors; however, to date, human cerebral epithelial cells (neuroepithelial cells) have not been shown to express NMDA receptor message or protein. In this study, human hypothalamic sections were examined for NMDA receptors (NMDAR) expression via immunohistochemistry and murine neuroepithelial cell line (V1) were examined for NMDAR via RT-PCR and Western analysis. We found that human cerebral epithelium express protein and cultured mouse neuroepithelial cells express both mRNA and protein for the NMDA receptor. These findings may have important consequences for neuroepithelial responses during excitotoxicity and in disease.

Expression of junctional proteins in human platelets

Platelets play a major role in thrombosis and hemostasis by binding the sub-endothelial matrix at sites of injury, but also participate in vascular pathologies such as atherosclerosis. Recently, junctional proteins like PECAM-I and JAM-family members have been recovered from platelets, therefore we examined what other junctional molecules may be present in platelets. We observed immunoreactivity for APC (147 kD), beta-catenin (92 kD), E-cadherin (120 and 84 kD) and occludin (70-85 kD) by western blotting. Additionally, beta-catenin, pan-reactive cadherins, E-cadherin and occludin were seen to partition with the triton insoluble cytoskeleton in platelets. These proteins were also found in a megakaryocyte (platelet precursor) line, MEG-01. Our data suggest that conventional junctional molecules are expressed in platelets and could possibly participate in aggregation, clot formation and wound healing.

TNF-alpha -induced endothelial cell adhesion molecule expression is cytochrome P-450 monooxygenase dependent

It is strongly suspected that cytokine-induced gene expression in inflammation is oxidant mediated; however, the intracellular sources of signaling oxidants remain controversial. In inflammatory bowel disease (IBD) proinflammatory cytokines, such as TNF-alpha, trigger gene expression of endothelial adhesion molecules including mucosal addressin cell adhesion molecule-1 (MAdCAM-1). MAdCAM-1 plays an essential role in gut inflammation by governing the infiltration of leukocytes into the intestine. Several groups suggest that endothelial-derived reduced NADP (NADPH) oxidase produces signaling oxidants that control the expression of adhesion molecules (E-selectin, ICAM-1, VCAM-1). In addition to NADPH oxidase, cytochrome P-450 (CYP450) monooxygenases have also been shown to trigger cytokine responses. We found that in high endothelial venular cells (SVEC4-10), multiple inhibitors of CYP450 monooxygenases (SKF-525a, ketoconazole, troleandomycin, itraconazole) attenuated TNF-alpha induction of MAdCAM-1, whereas NADPH oxidase inhibition (PR-39) did not. Conversely, E-selectin, ICAM-1, and VCAM-1 induction requires both NADPH oxidase and CYP450-derived oxidants. We show here that MAdCAM-1 induction may depend exclusively on CYP450-derived oxidants, suggesting that CYP450 blockers might represent a possible novel therapeutic treatment for human IBD.

Perverted head-shaking nystagmus: a possible mechanism

The authors describe a patient with acute MS who developed vertigo (tumbling) and downbeat nystagmus upon horizontal head oscillation (perverted head-shaking nystagmus). The only abnormality on brain MRI was a hyperintense signal in the caudal medulla that contains the nucleus Roller and nucleus intercalatus. These nuclei project to structures involved in the velocity storage system for horizontal vestibulocular reflex (VOR) and vertical VOR, and also to the vestibular cerebellum. The authors offer possible mechanisms for perverted nystagmus in this patient.

Elevated plasma endothelial microparticles in multiple sclerosis

OBJECTIVE

To assess endothelial dysfunction in patients with MS and to investigate whether plasma from patients with MS induces endothelial cell dysfunction in vitro.

BACKGROUND

Endothelial cell dysfunction may contribute to the pathogenesis of MS. Elevations of soluble adhesion molecules intracellular adhesion molecule, vascular cell adhesion molecule, and platelet-endothelial cell adhesion molecule-1 (CD31) have been reported as markers of blood-brain barrier (BBB) damage in MS, but direct assay of endothelium has been difficult. Endothelial cells release microparticles < approximately 1.5 microm (EMP) during activation or apoptosis. The authors developed a flow cytometric assay of EMP and studied EMP as markers of endothelial damage in MS.

METHODS

Platelet-poor plasma (PPP) from 50 patients with MS (30 in exacerbation and 20 in remission) and 48 controls were labeled with fluorescein isothiocyanate (FITC)-conjugated anti-CD31 and anti-CD51 (vitronectin receptor) antibodies, and two classes of EMP (CD31+ and CD51+) were assayed by flow cytometry. For in vitro studies, patients' plasma was added to the microvascular endothelial cell (MVEC) culture and release of CD31+ and CD51+ EMP were measured in the supernatant.

RESULTS

Plasma from patients in exacerbation had 2.85-fold elevation of CD31+ EMP as compared with healthy controls, returning to near control value during remission. The CD31+ EMP concentration showed a positive association with gadolinium enhancement in patients with MS. In contrast, CD51+ EMP remained elevated in both exacerbation and remission. This suggests that CD31+ EMP is a marker of acute injury, whereas CD51+ EMP reflects chronic injury of endothelium. MS plasma induced release of both CD31+ and CD51+ EMP from MVEC culture in vitro.

CONCLUSION

Endothelial dysfunction is evident during exacerbation of MS, evidenced by shedding of EMP expressing PECAM-1 (CD31). The in vitro data indicate contribution of one or more plasma factors in endothelial dysfunction of MS.

Adrenocortical carcinoma with cerebral metastasis in a child: case report and review of the literature

OBJECTIVE AND IMPORTANCE

Adrenocortical carcinoma (ACC) is rare in the pediatric population, and brain metastasis seldom occurs.

CLINICAL PRESENTATION

The authors report a case of metastatic ACC to the brain in a 9-year-old patient who had an adrenal cortex neoplasm removed at 4 years of age, and was free of symptoms for 5 years. Two weeks before admission she complained of blurred vision in both eyes.

INTERVENTION

Examination revealed bilateral papilledema, and a Magnetic Resonance Imaging (MRI) of the brain revealed a mass in the left lateral ventricle with extensive vasogenic edema and hydrocephalus. The tumor was removed, and histopathologic examination demonstrated metastatic ACC.

CONCLUSION

Although ACC is a rare neoplasm it must be considered in the differential diagnosis of cerebral lesions in patients with a history of this tumor. Periodic long-term brain imaging is suggested as part of the follow up in patients with adrenocortical neoplasms.

Liposuction and ischemic optic neuropathy. Case report and review of literature

Ischemic optic neuropathy occurred in a patient following liposuction. Perioperative anemia and hypotension may be the cause of this complication. Correction of anemia with transfusion improved the hemoglobin and hematocrit but the right eye remained blind. Liposuction should be added to the list of the surgical procedures that may produce ischemic optic neuropathy as an isolated complication.

Persisting aphasia as the sole manifestation of partial status epilepticus

OBJECTIVES

Persisting aphasia presenting as an isolated inability to vocalize is an uncommon presentation of simple partial status epilepticus and only eight such cases have been reported over the past 40 years.

METHODS

We studied a patient with a 5-year history of recurrent episodes of inability to talk, without any other motor or cognitive impairments. Episodes lasted as long as 24 h, interictal EEGs were normal and she was diagnosed as a conversion disorder.

RESULTS

EEG recordings during one of the episodes showed continuous discharges in the right frontal and parasagital areas demonstrating the ictal nature of the deficits. During the episode the patient had no deficits of strength, or in her ability to perform skilled movements to command, imitation or manipulation of objects. Comprehension of complex verbal commands was preserved and she would make attempts to articulate words and correctly answered questions with head nodding or monosyllables, yes or no. She could hum but had no other vocalizations.

CONCLUSIONS

This is the first case of aphasic status epilepticus secondary to epileptogenic discharges of the right hemisphere. The case is also unique for the isolated involvement of production of language during the seizure.

Case report: one-and-a-half-syndrome and tuberculosis of the pons in a patient with AIDS

A patient with advanced AIDS presented with right conjugate gaze palsy and impaired adduction on left gaze (the one-and-a-half syndrome). The responsible pontine lesion involved the ipsilateral abducens nucleus and the adjacent medial longitudinal fasiculus (MLF), as demonstrated by magnetic resonance imaging (MRI). Tuberculosis (TB) was the etiology of the brainstem lesion. The patient had complete recovery after anti-tuberculosis treatment. The nuclear location of the tuberculoma is unusual and the reversal of this neuro-ophthalmologic syndrome is noteworthy.

Cerebral ventricles are smaller in Hispanic than non-Hispanic patients with Alzheimer's disease

MRI scans were compared between 71 Hispanic and 73 white non-Hispanic patients with National Institute of Neurological Disorders and Stroke probable AD. Analysis of covariance controlled for age, sex, education, and Mini-Mental State Examination scores indicated that ventricular size was smaller in Hispanic than white non-Hispanic patients (p = 0.0003). There was no difference in cortical atrophy and T2-weighted white matter hyperintense signals between groups.

The use of dopamine agonists in very elderly patients with Parkinson's disease

BACKGROUND

Controversy exists regarding the use of dopamine receptor agonists in elderly patients with Parkinson's disease because of concern about a high rate of intolerable side effects.

METHODS

A retrospective chart review was used to examine our experience with dopamine agonist use in the very elderly by identifying patients in our Parkinson's disease database who were over the age of 80 years and who had received agonists. Sixty-nine patients were identified who had 120 separate trials of agonist therapy. Successful treatment with the agonist was defined as maintenance of the agonist for a minimum of 6 months.

RESULTS

The overall success rate among the very elderly for an agonist trial was 46%. Success rates for individual agonists were 15 of 27 (56%) bromocriptine, 18 of 34 (53%) pergolide, 17 of 43 (40%) pramipexole, and 5 of 16 (31%) ropinirole. In successful trials with bromocriptine, the mean daily dose was 12.8 mg, mean duration of treatment was 40 months, and mean age at drug initiation was 82 years; for pergolide it was 1.8 mg, 32 months, and 83 years; for pramipexole 2.7 mg, 14 months, and 83 years, and for ropinirole 10.6 mg, 11 months, and 83 years.

CONCLUSION

This study demonstrated that therapeutic dosages of dopamine agonists were well tolerated by 46% of very elderly patients who received a trial of an agonist. These results indicate that dopamine receptor agonist therapeutic trials are warranted in selected very elderly patients.

Glossopharyngeal neuralgia and MS

Glossopharyngeal neuralgia (GPN) is characterized by a severe lancing pain in the posterior pharynx, tonsillar fossa, and base of the tongue. It is induced frequently by swallowing and yawning. GPN has not been described previously in MS patients. The authors report four MS patients with GPN. Three responded to carbamazepine and one resolved during treatment with adrenocorticotrophin hormone (ACTH) and cyclophosphamide. Withdrawal of carbamazepine after 1 week in one patient resulted in recurrence of pain. GPN may be associated with MS and responds to carbamazepine.

Reduction of Relapses in Multiple Sclerosis after Anti-Alpha4 Integrin Antibody (Natalizumab)

Anti-alpha4 integrin antibody, natalizumab (Antegren), is a monoclonal antibody to a4b1 integrin adhesion molecules expressed on activated monocytes and CD4 cells. A 1-year followup of 28 patients with relapsing multiple sclerosis, randomized to 3 groups in a double-blind pharmacokinetic study, are presented. One group received placebo, a second group low doses (0.01–0.3 mg/kg) of natalizumab, and a third group high doses (1–3 mg/kg) of natalizumab. The observed reduction of relapses in all natalizumab-treated patients with multiple sclerosis suggests a potential range of doses to induce stabilization of the disease.

The effect of pregnancy in Parkinson's disease

Pregnancy in patients with Parkinson's disease (PD) is a rare occurrence. Previous reports based on retrospective analysis suggest that pregnancy may have a deleterious effect on PD. We describe the effects of pregnancy on the symptomatology of a 33-year-old woman with PD using quantitative neurologic and quality-of-life scales prepartum, intrapartum, and postpartum. During her pregnancy, she was only treated with carbidopa/levodopa. The pregnancy resulted in a normal full-term vaginal delivery of a healthy infant. Significant worsening of this patient's motor symptoms occurred during pregnancy without return to baseline at 15 months postpartum. Pregnancy may exacerbate PD and may have a long-term negative impact on the course of the illness. This report may assist physicians in the counseling of patients with young-onset PD who wish to consider pregnancy.

Amantadine-induced peripheral neuropathy

We report a 48-year-old woman with a 17-year history of PD who developed a peripheral sensory-motor neuropathy secondary to chronic administration (8 years) of amantadine. Discontinuation of amantadine resulted in resolution of trophic skin ulcers, paresthesias, and distal weakness. Amantadine may be hazardous to patients with severe and chronic livedo reticularis.

Bilateral infarction in the territory of the anterior cerebral arteries

An elderly hypertensive man had extensive bilateral infarction in the distribution of the anterior cerebral arteries. The circle of Willis was fully formed, but occlusion of the dominant anterior cerebral artery, aggravated and perhaps caused by postlaparotomy hypotension, produced the dramatic lesions, causing akinetic mutism. This stroke pattern occurs in various settings and does not require an anomalous azygous unilateral supply to both anterior cerebral arteries.

Pramipexole in progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is a progressive neurodegenerative disorder with no effective treatment. Dopaminergic agents occasionally produce transient symptomatic improvement. The authors report the results of pramipexole treatment (4.5 mg daily) in six patients with PSP (average disease duration, 4.4 years). Patients were treated for 2 months. Patients were evaluated with the Unified Parkinson's Disease Rating Scale, Hoehn and Yahr stage, and Schwab and England Activities of Daily Living Scale at baseline and 2 months. Pramipexole was not efficacious for the symptoms of PSP.

Skin eruption with gabapentin in a patient with repeated AED-induced Stevens-Johnson's syndrome

Skin eruptions have been reported with the use of all antiepileptic drugs and there is a significant risk of cross-reactivity between these agents in causing serious eruptions such as Stevens-Johnson's syndrome. Gabepentin is usually considered a safe agent for patients with a previous history of drug allergies and there have been no cases of skin eruption reported to the gabapentin post marketing surveillance. We report a patient who had severe Stevens-Johnson's syndrome induced by phenytoin and later by carbamazepine. Subsequent use of gabapentin also resulted in a skin eruption which was limited to the lower extremities but without systemic or mucosal involvement. This case suggests that patients with a strong history of drug-induced idiosyncratic reactions may experience such reactions to gabapentin as well.